עברית

Vulnerability Intelligence

CVE-2026-63867

High 8.2

Published
Last modified
NVD status
Analyzed

Description

In the Linux kernel, the following vulnerability has been resolved: mptcp: close TOCTOU race while computing rcv_wnd The MPTCP output path access locklessly the MPTCP-level ack_seq in multiple times, using possibly different values for the data_ack in the DSS option and to compute the announced rcv wnd for the same packet. Refactor the cote to avoid inconsistencies which may confuse the peer. Also ensure that the MPTCP level rcv wnd is updated only when the egress packet actually contains a DSS ack.

Affected products

linux: linux kernel

References7

Metrics

CVSS 3.1
8.2 HIGH Score source: CNA CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
EPSS — exploit probability
0% percentile: 20 · as of 14 November 2026
CWE
CWE-367CWE-362

Could this be exploited in your environment?

A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.